One officer described how car thieves might pretend to be beggars, sifting through curbside trash. “If someone is in the middle of a dark street, staring into the car and then when we drive by, they start ripping up garbage bags,” the police officer, Michael Noboa, said, “that would give me reasonable suspicion to conduct a stop, question” and possibly frisk.

Another officer in the same Brooklyn precinct, Kha Dang, explained how gang members often stash a gun nearby when they congregate outdoors. So he might grow suspicious, he explained, if he observed people repeatedly glancing over at a trash can or “at the bushes, you know, no person would sit there and keep looking at the bushes like that.”

. . .

Officer Gonzalez said he might grow suspicious if someone were waiting at a bus stop and “every possible bus that they could possibly get on has come through and went, and this person is still there.”

Officer Dang said that men “randomly looking in apartment windows” had led to a number of stops.